PB2173: THE EFFECT OF RUXOLITINIB THERAPY ON HEMOSTATIC PARAMETERS IN PATIENTS WITH PRIMARY MYELOFIBROSIS
Authors: Natalia Korsakova, Natalia Silina, Olga Golovina, Elizaveta Efremova, Sergey Voloshin, Ludmila Papayan
Journal: HemaSphere (2023)

Topic: 15. Myeloproliferative neoplasms - Biology & Translational Research Background: JAK-kinase inhibitors get increasingly widespread in various hematological malignancies treatment due to their direct disease pathogenesis influence. Ruxolitinib is shown to have a positive effect in patients with such Ph-negative myeloproliferative neoplasm as primary myelofibrosis (PMF), demonstrating durable reduction in splenomegaly and improvement in the total symptom score. However the influence of ruxolitinib treatment on coagulation parameters in PMF is not sufficiently studied, whereas patients´ hemostatic status is important to consider for thrombotic and bleeding complications prevention. Aims: To evaluate plasma coagulation parameters in ruxolitinib-treated patients with primary myelofibrosis compared with non-treated and treated with other medications PMF patients. Methods: The study group consisted of 13 patients with PMF treated with ruxolitinib with or without hydroxyurea (HU) and/or acetylsalicylic acid (ASA). The other groups used for comparison included 7 PMF patients treated with HU with or without ASA, 10 PMF patients treated with ASA and 11 PMF patients without treatment with any medications at least 10 days before enrollment. Control group included 37 practically healthy volunteers. All individuals gave informed consent for participation in the study. Fibrinogen concentration and FVIII activity assessment was performed in platelet poor plasma using clotting methods on automatic coagulometer according to the manufacturer’s recommendations. Statistical data processing was performed using STATISTICA 6.0. The results were presented as median and interquartile interval. Kruskal-Wallis H-test was used for patient groups comparison, the differences were considered statistically significant at p<0.05. Mann-Whitney U-test was used to compare patient groups with controls and in pairs with each other, corrected critical levels of statistical significance were p´=0.0127 and p´=0.0085 accordingly. Results: Among plasma hemostatic parameters the most marked differences depending on therapy were shown in fibrinogen concentration and FVIII activity (Table 1). Upon that, PMF patients treated with ruxolitinib had the most prominent increase in these two parameters that exceeded significantly controls (in both cases) and non-treated patients with PMF (fibrinogen concentration), FVIII activity tended to increase compared with non-treated patients and patients treated with ASA.Summary/Conclusion: Fibrinogen concentration growth and pronounced tendency of FVIII activity increase in ruxolitinib-treated PMF patients can indicate hypercoagulation changes reinforcement accompanying such therapy that suggests prothrombotic state development and risk of thrombosis. Further investigations with observation in dynamics are required to determine the role of target therapy in prothrombotic changes development in patients with primary myelofibrosis. Keywords: Ruxolitinib, Hemostasis, Myelofibrosis, Myeloproliferative disorder